Evidence map›Paper›PMID 41494244›Full record

ArticleDrug metabolism and disposition: the biological fate of chemicals2026

Mass spectrometry footprinting reveals microsomal CYP2A6 structural changes induced by interaction with its reductase flavin mononucleotide domain.

Mengqi Chai, Sarah D Burris-Hiday, Don L Rempel, Michael L Gross, Emily E Scott

Abstract read
In one paragraph

Article in Drug metabolism and disposition: the biological fate of chemicals, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Mengqi ChaiDepartment of Chemistry, Washington University in St. Louis, St. Louis, Missouri.
Sarah D Burris-HidayDepartment of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan.
Don L RempelDepartment of Chemistry, Washington University in St. Louis, St. Louis, Missouri.
Michael L GrossDepartment of Chemistry, Washington University in St. Louis, St. Louis, Missouri. Electronic address: mgross@wustl.edu.
Emily E ScottDepartment of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan; Departments of Pharmacology and Biological Chemistry, Programs in Biophysics and Chemical Biology, University of Michigan, Ann Arbor, Michigan. Electronic address: scottee@umich.edu.

Funding

INTERDEPARTMENTAL TRAINING IN PHARMACOLOGICAL SCIENCEST32GM007767 · NIGMS · UNIVERSITY OF MICHIGAN AT ANN ARBOR · PI ISOM, LORI L. · 1985 to 2019
$10.2M
NEW CHEMICAL PROBES ENABLE MASS SPECTROMETRY-BASED FOOTPRINTING OF HUMAN PROTEIN STRUCTURE IN LIPID MEMBRANES AND CELLSR01GM131008 · NIGMS · WASHINGTON UNIVERSITY · PI MICHAEL L GROSS, Weikai Li · 2019 to 2026
$3.8M
Structural Basis of Cytochrome P450 Activity-Equipment SupplementR37GM076343 · NIGMS · UNIVERSITY OF MICHIGAN AT ANN ARBOR · PI SCOTT, EMILY E · 2015 to 2024
$3.7M
Structure/Function of Potential Human Cytochrome P450 Drug TargetsR35GM158062 · NIGMS · UNIVERSITY OF MICHIGAN AT ANN ARBOR · PI Emily E Scott · 2025 to 2026
$1.2M
NIGMS NIH HHS R01 GM131008NIGMS NIH HHS R35 GM158062NIGMS NIH HHS R37 GM076343NIGMS NIH HHS T32 GM007767
6 · The paper itself

Abstract

NADPH cytochrome P450 reductase is the required redox partner for the majority of human cytochrome P450 enzymes, which are critically important for phase I drug metabolism of a wide variety of substrates. It is well understood that cytochrome P450 reductase supports P450 catalysis when its flavin mononucleotide (FMN)-containing domain (FMND) binds to the proximal side of P450 enzymes to deliver electrons to the P450 heme. Herein, we describe mass spectrometry-based footprinting approaches to compare the surface labeling of CYP2A6 and that of an artificial fusion protein composed of the reductase FMND linked to the N-terminus of CYP2A6 (FMND/CYP2A6). Three complementary footprinting approaches were used: hydrogen-deuterium exchange, benzoyl fluoride labeling, and fast photochemical oxidation of proteins (FPOP). Although the different labeling approaches target different amino acids and occur over varying reaction timescales, their outcomes generally agree. These experiments did not detect differential protection on the proximal P450 face where FMND is expected to bind. Instead, they consistently demonstrated increased exposure of CYP2A6 surface residues, indicative of structural changes in CYP2A6 in the presence of the FMND. Overall, the reduced protection is consistent with the FMN domain causing long-range allosteric modulation of the CYP2A6 structure. This structural evidence is consistent with increasing functional evidence that the reductase is an allosteric modulator of P450 enzymes in addition to its role in electron transfer. SIGNIFICANCE STATEMENT: Both established and new mass-spectrometry footprinting methods support structural changes in the CYP2A6 structure upon interaction with the FMN-containing domain of its reductase. This evidence supports the idea that the reductase is an allosteric modulator of P450 enzymes, in addition to its established role in electron transfer.

Indexed as

Cytochrome P-450 CYP2A6Flavin MononucleotideHumansMass SpectrometryNADPH-Ferrihemoprotein ReductaseOxidation-ReductionProtein BindingProtein DomainsProtein FootprintingCYP2A6 protein, humanCytochrome P-450 CYP2A6Flavin MononucleotideNADPH-Ferrihemoprotein ReductaseBenzoyl fluoride footprintingCytochrome P450 2A6 (CYP2A6)Fast photochemical oxidation of proteinsHydrogen-deuterium exchangeMass spectrometry footprintingNADPH-cytochrome P450 reductase

Identifiers

PMID41494244
PMCPMC12881669

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.